Take a piece of paper that you are done using. Crumple it up into a ball. Now gently open up the paper, but don't flatten it out completely. The highest points
on the paper represent the mountaintops and the lowest wrinkles, the valleys. Choose one color of water-soluble marker and use it to mark the highest points
on the map. These points are the mountain ridgelines. Choose a second color
and mark the places where different bodies of water might be: creeks, rivers, and lakes. With a third color, mark four or five places to represent human settlements: housing tracts, factories, shopping centers, office buildings, schools, etc. Try sprinkling a powdered material, such as cinnamon, red pepper, or cocoa powder, to demonstrate how pollutants flow through the watershed. Use spray bottles to lightly spray the topographic watershed maps. The spray represents water falling into the watershed (Source: VA Love-A-Tree).